Barcelona have criticised the behaviour of their own supporters for a banner and a series of chants which were targeted at Espanyol during Sunday's 4-1 win in the Catalan derby at the Camp Nou.
A small section of the home fans unveiled a banner during the game making a derogatory reference to the new Chinese ownership at Espanyol.
In addition, there were regular anti-Espanyol chants throughout the game, which was settled courtesy of two Luis Suarez goals and one each for Jordi Alba and Lionel Messi.
"We don't want signs like that appearing or people singing offensive chants," Barca president Josep Maria Bartomeu said in a news conference on Tuesday.
"We want to have respect for everyone. We made an official announcement regarding the situation. We regret what happened and we apologised because it is not something we wanted to see.
"It was the same against [Real] Madrid [during the Clasico]. There were people singing things which shouldn't have been sung and some fans were temporarily removed. The Camp Nou should be a place of respect and we're disappointed."
Prior to Bartomeu's appearance to review the calendar year, during which a large portion of his time was dedicated to talking about Lionel Messi's contract situation, the club had released a statement on the banner and the chants in question.
"The Board of Directors condemns the offensive chants and the banner displayed at Camp Nou against RCD Espanyol which contravenes the singing section's rules on behaviour," the statement read.
"These actions are not the first incident. In the last game against Real Madrid played at the Camp Nou there were offensive chants directed at the rival.
"Following these incidents a [supporters' group] opened four disciplinary records following consultation with the club and the police. Three of the people ended up being permanently banned from the singing section and the remaining person was banned for three games."
Barca could yet be punished for Sunday's events. Espanyol were fined €24,002 after their fans displayed a number of banners insulting Gerard Pique, his partner Shakira, and Lionel Messi during a Copa del Rey game against Barca earlier this year.